Warp tension device for looms

ABSTRACT

The device comprises a compensating roller made in the form of a feed worm which in its cross section has the shape of a rhomb with rounded vertices. On either side of the roller there are mounted warp guide rods oriented relative to said roller so, that when the shed is crossed, formed between them is a compensation loop which is drawn out when the shed is fully open.

United States Patent Selivanov et al.

[ 1 Sept. 18, 1973 WARP TENSION DEVICE FOR LOOMS Inventors: AnatolyGrigorievich Selivanov,

ulitsa Lobachecskogo, 44, kv. 59; Nikolai Ivanovich Makachev, ulitsaTatischeva, l7, kv. 33; Maria Kuzminichna Parshina, ulitsa Tsjurupy, I2,korpus l, kv. 27, all of Moscow, USSR.

Filed: Jan. 6, 1972 Appl. N0.: 215,738

US. Cl. 139/97 Int. Cl. D03d 49/04, D03d 47/26 Field of Search 139/97,98, I2, 24,

References Cited UNITED STATES PATENTS Rossmann 139/12 3,483,897 l2/l969Pfarrwaller I39/98 2,649,864 8/I953 Mayer, Jr. et al. I39/97 2,932,3254/1960 Patrick 139/97 FOREIGN PATENTS OR APPLICATIONS 1,237,034 6/1960France 139/12 6,332 1905 Great Britain 134,418 9/l902 Germany 139/24Primary Examiner-James-Kee Chi Attorney.l0hn G. Schwartz [57] ABSTRACTThe device comprises a compensating roller made in the form of a feedworm which in its cross section has the shape of a rhomb with roundedvertices. On either side of the roller there are mounted warp guide rodsoriented relative to said roller so, that when the shed is crossed,formed between them is a compensation loop which is drawn out when theshed is fully open.

4 Claims, 6 Drawing Figures PATENTEI] SE?! 8 I973 SHEET 1 0F 2 PATENTEDSEP] 8 I975 SHEET 2 0F 2 WARP TENSION DEVICE FOR LOOMS The presentinvention relates to travelling wave shedding looms, and more preciselyto warp tension devices employed in these looms.

This invention can be most advantageously used in travelling wave loomsproducing fabrics of various articles.

Known at present are warp tension devices, comprising shaft rods withhealds for the passage of the warp threads, and a compensating rollerlocated parallel to the shaft rods and having a surface which simulatesthe shed wave profile, and contacts the warp threads, to compensate fortension variations.

In said mechanism said roller is made sectional, and consists of an axlewhereon collected are eccentric washers with collars shifted relative toeach other (see, for example, a Swiss Pat. No. 455667, dated 1963).

In said devices, the roller made in the form of an axle with eccentricwashers collected thereon does not permit regulating the tension of thewarp threads, which is necessary when changing to another article offabric to be produced; in the latter case the assembled roller must bereplaced. Besides that, employment of the eccentric washers lengthensthe friction distance for the warp threads.

It is an object of the present invention to eliminate the citeddisadvantages.

An important object of the invention is to provide a warp tensiondevice, that would permit manufacturing a wide variety of fabrics withrequired tension due to the possibility of regulating the warp threadstension, and would enable varying the profile of the shed wave formed bythe warp threads.

With these and other objects in view, in a warp tension device fortravelling wave shedding looms, comprising shaft rods with healds forthe passage of the warp threads, and a compensating roller having asurface which simulates the profile of the shed wave and contacts thewarp threads, to compensate for tension variations, according to theinvention, the compensating roller is made in the form of a feed worm,the cross section of which has a rhombic shape with rounded ver ticeswhose radii are chosen so, that the worm surface contact the warpthreads with minimum friction, and mounted on either side of the rollerare warp guide rods capable of vertical displacement and orientedrelative to said roller so, that when the shed is crossed, acompensation loop is formed between the rods and the roller, and whenthe shed is fully open the loop is drawn out.

Such a design permits producing a wide variety of fabrics due to thevertical displacement of the rods with respect to the roller, to changetension in the fabric forming zone. Besides, it will also enablereducing the path of friction of the warp threads against the elementsof the compensator, and setting the required shed wave profile.

The screwed surface of the roller should advantageously be helicallyshaped. Such a surface shape of the roller is used with a smooth shedwave, since in this case the warp threads form a voluminous space forthe shuttle to fit therein more freely.

The screwed surface of the roller may also have a stepped form. Thismakes possible advanced shed crossing, which is vital for a certaingroup of fabrics.

In said device, the guide rods can be capable of vertical displacement,to vary the warp tension. This is necessary to change warp tension whenpassing to another sort of fabric.

For a better appreciation of the invention, considered below is aparticular illustrative embodiment thereof with references to theappended drawings, wherein:

FIG. I is the threading diagram of a travelling wave loom with the warptension device according to the invention;

FIG. 2 shows a warp tension device with a stepped roller;

FIG. 3 is an enlarged view of the stepped roller in section;

FIG. 4 is section IV-IV in FIG. 2;

FIG. 5 shows another version of the warp tension device;

FIG. 6 is section VIVI in FIG. 5.

GENERAL DESCRIPTION OF THE WARP TENSION DEVICE DETAILED DESCRIPTION OFTI-IE DEVICE The compensating roller 4 is disposed parallel to the shaftrods 1, and is made in the form of a stepped feed worm 6 (FIGS. 2, 3)which in its cross section has a rhombic shape with rounded vertices awhose radii are chosen so, that the worm surface contact the warpthreads with minimum friction. The worm surface simulates the profile ofthe shed wave and contacts the warp threads, to compensate for tensionvariations in these threads.

The stepped worm is formed by rhombic sections 7 which connect eachother through partitions 8 wherebetween the warp threads 3 are drawn in.

Each section 7 is phase-shifted to an angle a, as is shown in FIG. 3, sothat vertices a a a a of each section 7 form the shed waveconventionally shown in FIG. 2. The stepped worm 6 is mounted inbearings 9 and 10 which are placed on brackets 11, 12. The verticaldisplacement of the guide rods 5 (FIG. 4) is effected by means of screws13 with shoulders 14 which rest against plates 15. These plates areattached to the housings of bearings 9 and 10. Rods 5 are orientedrelative to roller 4 so, that when the shed is crossed, as is shown inFIG. 1, a compensation loop is formed between these rods and roller 4.When the shed is fully open, the loop is drawn out.

Shown in FIGS. 5 and 6 is another version of the compensating roller 4.

In this case the roller is made as a worm 16 which has a rhombic outlinein its cross section, and whose surface is helically shaped as shown inFIG. 5.

OPERATION OF THE WARP TENSION DEVICE Before setting the device inoperation, the travelling wave loom is threaded through. The warpthreads 3 are drawn into healds 2 passing about the back rest 17 (FIG.1). The required shed wave is set according to the article of fabric,the compensating roller being phased opposite to the shed wave.

The required tension of the warp threads 3 during the threading processis attained by displacing the guide rods 5 with respect to thecompensating roller 4, which is done by turning screws 13 with shoulders14.

As the shedding mechanism is in action and the shed is fully open, thecompensation loops formed by the guide rods 5 and the rhombic-shapedroller 4 yield the required length of warp threads into the sheddingzone, whereas when the shed is crossed the compensating roller 4 gathersthe excess length of the warp threads required for the shedding process,the warp tension all across the shedding zone remaining constant. Therhombic-shaped roller enables the friction path of the warp threads toinvolve minimum friction, and most fully maintains permanence of warptension in a travelling wave loom.

We claim:

1. A warp tension device for travelling wave shedding looms, comprising:shaft rods with healds for the passage of the warp threads; acompensating one-piece screwed roller located parallel to said shaftrods, and made in the form of a feed worm whose surface simulates theprofile of the shed wave and contacts the warp formed between the rodsand the worm, and when the shed is fully open the loop is drawn out, thelength of said warp threads to be compensated being substantiallyincreased and decreased dependent on the article of fabric to beproduced, the friction path of the warp thread along said roller beingsubstantially short and the load upon said roller being substantiallysmall, said warp thread remaining free from being wedged.

2. A device as claimed in claim 1, wherein the screwed surface of theroller follows a smooth helix;

3. A device as claimed in claim 1, wherein the screwed surface of theroller has a stepped shape;

4. A device as claimed in claim 1, wherein the guide rods are capable ofvertical displacement, to change tension of the warp threads.

1. A warp tension device for travelling wave shedding looms, comprising:shaft rods with healds for the passage of the warp threads; acompensating one-piece screwed roller located parallel to said shaftrods, and made in the form of a feed worm whose surface simulates theprofile of the shed wave and contacts the warp threads, to compensatefor tension variations, said worm having in its cross section the shapeof a rhomb with rounded vertices, the radii of which are chosen so thatthe worm surface contact the warp threads with minimum friction; warpguide rods mounted on either side of said roller, and oriented relativeto this roller so, that when the shed is crossed a compensation loop isformed between the rods and the worm, and when the shed is fully openthe loop is drawn out, the length of said warp threads to be compensatedbeing substantially increased and decreased dependent on the article offabric to be produced, the friction path of the warp thread along saidroller being substantially short and the load upon said roller beingsubstantially small, said warp thread remaining free from being wedged.2. A device as claimed in claim 1, wherein the screwed surface of theroller follows a smooth helix;
 3. A device as claimed in claim 1,wherein the screwed surface of the roller has a stepped shape;
 4. Adevice as claimed in claim 1, wherein the guide rods are capable ofvertical displacement, to change tension of the warp threads.